Introduction to home-brew Solar powered steam engines.
The heat is unbearable! The sun beats down upon us and turns our comfortable homes in solar powered ovens. In the winter it seems a God-send, but in the 80 degree weather of mid July, our air conditioners seem to be the only salvation we can find. Of course, when the air conditioners come on, the electric bill goes up, and the God-send is once again an unbearable burden. Alas, if only we could harness that colossal monster in the sky as easily in the summer as we could in the winter! Actually, it has been done for more than a century now. Solar steam started in France when they first lit up Paris, and it turns out that it is really quite simple for us to do on a small scale... although perhaps a bit dangerous.
There are, as I'm sure you well know, the standard alternatives such as solar panels, and the time tested wind and water mills, which are exciting and simple projects. Did you know, though, that you can harness that great juggernaut of the industrial revolution, the steam engine? Yes, gentle reader, right in your own back yard, from throw-away junk, you too can be a user of our most common method of electrical production, steam power!
The first step in your project is a basic understanding of how a 2 cycle engine works. It's quite simple. Gas, air, and oil mixed together are allowed to enter the engine on the first stroke, and are exploded by a spark plug on the second stroke to produce usable power. This process is then repeated, until the stench overwhelms you and you need to lie down.
Now that you understand how the engine works, you will want to procure for yourself a cheap one. Preferably, you will get yourself a free one, as even one that is thought to be broken, will most likely run for our purposes. Got one? Good. Now on to step two.
Ramble down to the local hardware store and head to the plumbing supplies. You are looking for what is known as a "Check valve". This allows water to flow in one direction, but not the other, via the use of a little swinging door in the valve. You will need you valve to screw into the spark plug port on your engine, so make sure you find the right reducers if you can't find a valve that fits. Don't forget to buy some Teflon tape, as well, to seal up any leaks.
Next you will need a smooth metal or carbon rod that will fit inside of the check valve and not jiggle about too much. get one that is four inches long, so that you can cut it to the size you need. The longer the better, really.
Now that you've got all these things, you can put your engine together. Remove the spark plug from the engine, place the rod on top of the piston, and screw your check valve on over it. Cut the rod so that it opens the little door when the piston reaches the top of the cylinder, and you've got yourself a functioning steam engine! Easy, right? I knew you could do it.
Once you've got your engine, you're probably wonder what the heck your supposed to do with it. Well, I can't tell you, its a trade secret. Just kidding. Oh, that sun... You will now need an alternator or a generator to produce electrical power. Hooking this up to your engine is a bit beyond the scope of this article, so you'll have to look into that on your own. OR, failing that, you could do what I did and just find an old electrical generator with a 2 stroke engine already attached. Mine is 3400 watts and it was free of charge. Things of this nature can be found at junk yards, consignment shops, Craigslist.org, antique stores, etc. The search is half the fun.
Your engine will require a good sized wheel attached to it as well. This should be weighted on the outside of the wheel, and you attach it to the drive shaft, basically wherever is convenient. These are called "fly-wheels". The function of the fly wheel is to store your engines power while it is running, but before it is converted to electricity. Don't fret too much about the wheel size to begin with. As long as it is large enough to keep the shaft spinning, you should get some entertaining results. It is just junk we're playing with, after all.
Well, that was a lot of work, wasn't it? But step back and look at the result. You've got yourself a fully functioning power station! Oh wait, you're missing something. You need a source of power. A fat lot of good your engine will do without something to run it, eh? You do have options now, however. You will need a vessel, first and foremost, to contain the water. This should be capable of high pressures. You'll want it to be able to handle at least 2000 psi, for any real usable kind of power. And you'll need a heat source. For your vessel, I suggest and old scuba tank, or something akin to that. Paint ball guns have high pressure tanks on them, but won't hold very much water. Your choice of vessel is entirely up to you, and will require some real research, because high pressure steam will basically melt your face off, and that would really spoil the satisfaction you attained from the project.
Your vessel will require a "governor" to allow steam to escape if the pressure gets to high, and you will need a gauge, as well, to tell you how much pressure you've actually built in the tank. High pressure connections are also a must, and safety is the key here, so do your homework folks.
Finally, you're going to need a heat source. This can be anything from fire, to fission, but as you might have guessed from the title of this article, our interest is in the good old, labor free sun. To harness the amount of solar energy we would need to produce the power we're looking for, we will want a really big magnifying glass, or a large parabolic mirror. Since the magnifying glass isn't easily come by, I suggest we focus (get it?) on the mirror. This can be any large bowl shaped object, like a satellite dish, a home made design, or even one of those bowl shaped chairs. The important thing is that its cheap, or free. Next you will need to glue some reflective material, preferably mirrors, to the entire inner surface of your bowl. This will now focus a concentrated beam of sunlight where ever you point it, and you can use it to heat your vessel and make some steam! Fire up your engine and watch the juice flow.
There are, of course, certain logistical problems to this method of solar collection, like sunlight tracking. But cheap computers can be purchased to perform this task, or you could even just move the collector every hour or two to re adjust it. If you find this manner of solar collection to be a bit tedious, you can also use mother natures greatest solar collector, firewood. A good pile of wood under your boiler will produce excellent results, and with the aid of a gasifier you could be very efficient, indeed. That, however, is the subject of another article, and not meant for these pages. Enjoy your new found power, and stay cool!